The main protease (M^pro) of SARS-CoV-2 is an attractive target in anti-COVID-19 therapy for its high conservation and major role in the virus life cycle. The covalent M^pro inhibitor nirmatrelvir (in combination with ritonavir, a pharmacokinetic enhancer) and the non-covalent inhibitor ensitrelvir have shown efficacy in clinical trials and have been approved for therapeutic use. Effective antiviral drugs are needed to fight the pandemic, while non-covalent M^pro inhibitors could be promising alternatives due to their high selectivity and favorable druggability. Numerous non-covalent M^pro inhibitors with desirable properties have been developed based on available crystal structures of M^pro. In this article, we describe medicinal chemistry strategies applied for the discovery and optimization of non-covalent M^pro inhibitors, followed by a general overview and critical analysis of the available information. Prospective viewpoints and insights into current strategies for the development of non-covalent M^pro inhibitors are also discussed.

Studies have suggested that the nucleus accumbens (NAc) is implicated in the pathophysiology of major depression; however, the regulatory strategy that targets the NAc to achieve an exclusive and outstanding anti-depression benefit has not been elucidated. Here, we identified a specific reduction of cyclic adenosine monophosphate (cAMP) in the subset of dopamine D1 receptor medium spiny neurons (D1-MSNs) in the NAc that promoted stress susceptibility, while the stimulation of cAMP production in NAc D1-MSNs efficiently rescued depression-like behaviors. Ketamine treatment enhanced cAMP both in D1-MSNs and dopamine D2 receptor medium spiny neurons (D2-MSNs) of depressed mice, however, the rapid antidepressant effect of ketamine solely depended on elevating cAMP in NAc D1-MSNs. We discovered that a higher dose of crocin markedly increased cAMP in the NAc and consistently relieved depression 24 h after oral administration, but not a lower dose. The fast onset property of crocin was verified through multicenter studies. Moreover, crocin specifically targeted at D1-MSN cAMP signaling in the NAc to relieve depression and had no effect on D2-MSN. These findings characterize a new strategy to achieve an exclusive and outstanding anti-depression benefit by elevating cAMP in D1-MSNs in the NAc, and provide a potential rapid antidepressant drug candidate, crocin.

Objective:To investigate the rates of low disease activity and clinical remission in patients with systemic lupus erythematosus(SLE)in a real-world setting,and to analyze the related factors of low disease activity and clinical remission.Methods:One thousand patients with SLE were enrolled from 11 teaching hospitals.Demographic,clinical and laboratory data,as well as treatment regimes were collec-ted by self-completed questionnaire.The rates of low disease activity and remission were calculated based on the lupus low disease activity state(LLDAS)and definitions of remission in SLE(DORIS).Charac-teristics of patients with LLDAS and DORIS were analyzed.Multivariate Logistic regression analysis was used to evaluate the related factors of LLDAS and DORIS remission.Results:20.7％of patients met the criteria of LLDAS,while 10.4％of patients achieved remission defined by DORIS.Patients who met LLDAS or DORIS remission had significantly higher proportion of patients with high income and longer disease duration,compared with non-remission group.Moreover,the rates of anemia,creatinine eleva-tion,increased erythrocyte sedimentation rate(ESR)and hypoalbuminemia was significantly lower in the LLDAS or DORIS group than in the non-remission group.Patients who received hydroxychloroquine for more than 12 months or immunosuppressant therapy for no less than 6 months earned higher rates of LLDAS and DORIS remission.The results of Logistic regression analysis showed that increased ESR,positive anti-dsDNA antibodies,low level of complement(C3 and C4),proteinuria,low household in-come were negatively related with LLDAS and DORIS remission.However,hydroxychloroquine usage for longer than 12 months were positively related with LLDAS and DORIS remission.Conclusion:LLDAS and DORIS remission of SLE patients remain to be improved.Treatment-to-target strategy and standar-dized application of hydroxychloroquine and immunosuppressants in SLE are recommended.

ObjectiveDisruption of epithelial layer may instantaneously induce the generation of endogenous electric fields, which was proved to play an important role in guiding the cell migration and promoting wound healing. PIEZO1 is a kind of mechanic sensitive channel, may be regulated by voltage, is proved to involve in chemotactic migration of cells and play an important role in the process of wound healing. In this paper, the role of PIEZO1 and its downstream proteins FAK and integrin β1 in the electric field guided cell migration were investigated by HaCaT cells (human immortalized keratinocyte). MethodsCell migration was tracked by Living Cell Imaging System in directed current (DC) electric field (EF). Inhibitors and RNAi techniques were applied to study the function of PIEZO1 and other related proteins in electric fields. Western blot was used to detect the expression and phosphorylation levels of integrin β1 and FAK in electric field guided migration under EF stimulation. ResultsPiezo1 RNAi as well as Ruthenium red and GsMTx4 treatment all significantly inhibited the electrotaxis of HaCaT cells. Electric field stimulation with GsMTx4 treatment alone increased FAK phosphorylation level and the expression of integrin β1. Electric field promoted the expression level of integrin β1 and the phosphorylation level of FAK. Inhibiting the expression of PIEZO1 by RNAi significantly attenuated the phosphorylation level of FAK under EF stimulation. Inhibition of integrin β1 and FAK by inhibitor significantly decrease the electric field guided cell migration. ConclusionPIEZO1 as well as integrin β1 and FAK are involved in the electric field guided cell migration of HaCaT cells. Electric field signals regulate the expression of integrin β1 and the activation of FAK through PIEZO1-mediated signal pathway to orchestrate cell migration.

ObjectiveTo simulate the microstructure and mechanical properties of tendon tissue and promote its regeneration and repair, electrospinning technology was used to prepare L-polylactic acid (PLLA) fiber membranes loaded with different nano zinc oxide contents and with oriented structures. Physical and chemical characterization and biological performance evaluation were carried out to explore their effects on tendon cell proliferation and differentiation. MethodsPreparation of PLLA fiber scaffolds and PLLA/ZnO fiber scaffolds containing different mass fractions of nano ZnO was performed using electrospinning technology. The physicochemical properties of the scaffold were characterized by scanning electron microscopy, mechanical stretching, and EDS spectroscopy. The scaffold was co-cultured with mouse tendon cells to detect its biocompatibility and regulatory effects on cell differentiation behavior. ResultsThe fiber scaffolds were arranged in an oriented manner, and zinc elements were uniformly distributed in the fibers. The tensile strength and Young’s modulus of PLLA/0.1%ZnO fiber scaffolds were significantly higher than PLLA fiber scaffolds. The number of cells on the surface of PLLA/0.1%ZnO fiber scaffold was significantly higher than that of the PLLA group, and the activity was better; mouse tendon cells exhibit directional adhesion and growth along the fiber arrangement direction. ConclusionThe oriented PLLA/0.1%ZnO fiber scaffold had excellent physicochemical properties, which can significantly promote the oriented growth, proliferation and differentiation of tendon cells. It is expected to be used for tendon tissue regeneration and repair in the future.

Objective To carry out rigid-body inverse dynamics modelling and analysis of a self-designed 6RSS parallel bio-inspired masticatory robot.Methods Firstly,the functions of kinematic variables including translational/rotational velocities and accelerations were derived for rigid-body inverse dynamics modelling.Secondly,the rigid-body inverse dynamics model was established with the Newton-Euler's law.Finally,the chewing motion trajectories of the oral health volunteers were tracked and numerical calculations were carried out in the case where the robot was subjected to a chewing reaction force.Results Numerical calculations showed that the driving torque and the constraint force of the robot peaked when the chewing reaction force was at its maximum.Conclusion The external force has a large impact on the inverse dynamics of the robot,and theoretical references are provided for the motion control and optimal design of the robot.[Chinese Medical Equipment Journal,2024,45(3):16-22]

Objective:To explore the disease spectrum and corresponding clinical indicators of infantile cholestasis so as to provide a basis for the diagnosis of this type of disease at an early stage.Methods:The clinical data was collected from 203 hospitalized children diagnosed with infantile cholestasis at the Department of Gastroenterology of Maternal and Child Health Care, Guiyang City, from January 2018 to March 2023, including 130 males and 73 females. Patients general condition, personal history, and blood biochemical test indicators, including liver and coagulation function, blood ammonia, blood lipid profile, blood sugar, TORCH, thyroid function, and others, were retrospectively analyzed after admission. Cholangiography and high-throughput gene sequencing were performed in certain patients. The etiology of the enrolled cases were analyzed. Children's clinical data were compared with distinct inherited metabolic liver diseases (Group A) and biliary atresia (Group B). The statistical analysis was conducted using the t-test, Mann-Whitney test, Kruskal-Wallis test, or χ2 test, according to different data. Results:In 33 cases, infectious factors—primarily CMV infection—were the etiology of cholestasis. Forty cases had aberrant bile duct development, primarily biliary atresia, choledochal cysts, and intrahepatic bile duct dysplasia. In 26 cases, genetic metabolic factors mainly included citrin protein deficiency, sodium-taurocholate co-transporting polypeptide deficiency, and Alagille syndrome. 11 cases had drug/poisoning factors (parenteral nutrition-associated cholestasis). 19 cases had idiopathic infantile cholestasis. Three cases had other factors; however, all of them had Kawasaki disease. 71 cases had an unclear diagnosis. There was no statistically significant difference in terms of gender and age between groups A and B ( P>0.05). The alkaline phosphatase (ALP) and bile acid levels were significantly higher in Group A than Group B, with a P<0.05, while the gamma glutamyltransferase (GGT), direct bilirubin (DBil), and albumin levels were lower than those in Group B, with a P<0.05. The cytomegalovirus infection rate was higher in Group B (62.50%) than Group A (34.62%), and the difference between the two groups was statistically significant ( χ2=3.89, P<0.05). The alanine aminotransferase, aspartate aminotransferase, GGT, DBil, and albumin were significantly lower in patients with citrin protein deficiency than those in patients with biliary atresia, while ALP, bile acid, and blood ammonia were higher than those in patients with biliary atresia. Patients with sodium-taurocholate co-transporting polypeptide deficiency had higher bile acid than patients with biliary atresia, while the DBil was lower than that in patients with biliary atresia, and the difference was statistically significant ( P<0.05). Conclusion:Infantile cholestasis etiology is diverse. ALP, bile acids, GGT, DBil, and albumin levels can serve as simple indicators for early-stage differentiation between inherited metabolic liver disease and biliary atresia. The cholestasis etiology should be determined as early as possible following biliary atresia exclusion by actively completing genetic metabolic gene detection.

Objective To investigate the effect of varying ureteral wall thickness(UWT)at the site of ureteral stones on the clinical efficacy of ureteroscopic lithotripsy(URL).Methods The clinical data of 164 patients with ureteral stones in our hospital were retrospectively analyzed.According to different UWT,the patients were divided into the mild thickening group(84 cases,UWT<3.16 mm),the moderate thickening group(31 cases,UWT 3.16 to 3.49 mm),and the severe thickening group(49 cases,UWT>3.49 mm),and the differences of clinical related indicators among the three groups were compared.Results The incidence of postoperative renal colic and leukocyte disorder in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,and the differences were statistically significant(P<0.05).The postoperative catheterization time in the mild thickening group and the moderate thickening group were shorter than that in the severe thickening group,and the incidences of secondary lithotripsy,residual stones and stone return to kidney in the mild thickening group and the moderate thickening group were lower than those in the severe thickening group,with statistically significant differences(P<0.05).The length of hospital stay and hospitalization cost in the mild thickening group and the moderate thickening group were shorter/less than those in the severe thickening group,with statistically significant differences(P<0.05).Conclusion With the increase of UWT(especially when UWT>3.49 mm),the incidence of postoperative complications and hospitalization cost of URL increase to varying degrees,and the surgical efficacy decreases.In clinical work,UWT measurement holds potential value in predicting the surgical efficacy and complications of URL.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Objective:To investigate the CD163 expression characteristics in intracranial aneurysm (IA) tissue and blood of patients with IA and its feasibility as an early clinical screening indicator for IA.Methods:A total of 28 patients with IA admitted to Department of Neurosurgery, First Affiliated Hospital of Xinjiang Medical University from January 2021 to November 2023 were selected as IA group, and 28 healthy subjects from Health Management Center, First Affiliated Hospital of Xinjiang Medical University at the same time period were selected as control group. Eight saccular IA tissues and 12 superficial temporal artery tissues were collected from patients from IA group accepted IA clipping, and real-time fluorescent quantitative PCR (RT-qPCR) was used to detect the CD163 mRNA expression in these tissues. RT-qPCR was also used to detect the CD163 mRNA expression in the blood of the 2 groups. Seven patients with IA and 7 control subjects from the above 2 groups were randomly selected, respectively; and plasma CD163 protein content was detected by enzyme-linked immunosorbent assay (ELISA). Multivariate Logistic regression was used to analyze the influencing factors for IA. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic values of blood CD163 mRNA expression and plasma CD163 protein content in IA. Results:CD163 mRNA expression in IA tissues was significantly higher than that in superficial temporal artery tissues (41.870±20.355 vs. 6.080±5.444, P<0.05). CD163 mRNA expression in the blood of IA patients was significantly higher than that in the controls (1.969[1.124, 2.318] vs. 1.124[0.933, 1.379], P<0.05). CD163 mRNA expression in the blood of ruptured IA group, unruptured IA group, and control group was gradually decreased, with significant differences ( P<0.05). CD163 mRNA expression in the blood of female IA patients was not statistically different compared with that in male IA patients ( P>0.05). ELISA showed that the CD163 protein content in plasma of the IA group was significantly higher than that in the control group [10.537±1.879] ng/L vs. [8.598±0.885] ng/L, P<0.05). Multivariate Logistic regression analysis showed that age and CD163 mRNA expression in the blood were independent influencing factors for IA occurrence ( OR=0.844, 95% CI: 0.750-0.951, P=0.005; OR=0.111, 95% CI: 0.024-0.506, P=0.004). ROC curve showed that the area under the curve (AUC) of CD163 mRNA expression in blood in diagnosing IA was 0.759 (95% CI: 0.618-0.890, P=0.002), and that of CD163 protein content in plasma in diagnosing IA was 0.864 (95% CI: 0.610-1.000, P=0.035). Conclusion:CD163 mRNA expressions in blood and IA tissues and CD163 protein content in plasma are high in patients with IA; CD163 mRNA expression in blood is an independent risk factor for IA; CD163 protein in plasma can be used as a molecular marker for screening IA.